Conventionally, in image forming apparatuses such as copying machines, printers, and the like, a paper feed cassette is provided that stores recording paper supplied to an image forming portion. Ordinarily, in order for it to be possible to refill and exchange recording paper in this paper feed cassette, it is installed so that the paper feed cassette can be inserted and removed from the main body of the image forming apparatus. Also, this paper feed cassette is provided with a rotating board (also referred to as a lift board) that can rotate in the vertical direction while supporting the recording paper. A coil spring is disposed on the underside of this rotating board, and biasing force is conferred on the rotating board in the upward direction by this coil spring. Therefore, when the paper feed cassette loaded with paper is inserted in the main body of the image forming apparatus, the uppermost sheet of recording paper faces or makes contact with a pickup roller, and it is possible for paper to be supplied from the paper feed cassette toward an image forming portion by the rotation of this pickup roller.
On the other hand, in this type of image forming apparatus, the achievement of a reduction in the installation space of the apparatus has been sought, and in response, image forming apparatuses have been developed wherein a paper feed portion (the paper feed cassette) is disposed in the lower portion, an original capturing portion (scanner portion) is disposed in the upper portion, and an image forming portion (print portion) and a discharge portion (discharge tray) are provided between the paper feed portion and the original capturing portion. That is, a reduction in the installation space of the image forming apparatus is achieved by adopting a configuration such that the discharge tray does not protrude in the lateral direction of the apparatus. Also, in this image forming apparatus, the paper feed cassette, the scanner portion, and the print portion are arranged in the shape of a sideways U in a front perspective of the apparatus. Therefore, the discharge tray is configured as an intermediate space open in the lateral direction (one side of the sideways U shape is open), and printed materials discharged to this intermediate space portion are removed from the front side or the lateral side (the open side described above) of the apparatus.
However, in an image forming apparatus with this sort of configuration, because the paper feed cassette is disposed in the lower portion of the apparatus, when the user wants to check the amount of paper remaining in the paper feed cassette, he must, in a bent over posture, pull the paper feed cassette out of the main body of the image forming apparatus and visually check the remaining paper. Particularly, when the user is a disabled individual, this checking operation is extremely bothersome and requires time.
Also, when the image forming apparatus stops during a printing operation, it is necessary for the user to check the reason for the stop, and afterwards take action to deal with the problem, and when the cause of the stoppage is an exhausted supply (during a printing operation there is no paper remaining in the paper feed cassette), after pulling out the paper cassette and visually confirming that there is no paper remaining, as described above, the user prepares paper and refills the paper feed cassette. This action requires a long period of time, during which print jobs are erased, and when there are image forming requests from other users during that period of time, multiple print jobs accumulate in the memory of the image forming apparatus, and an insufficient memory status may result.
As a way of solving this problem, for example, JP 2000-313533A discloses technology wherein when there is no paper remaining in the paper feed cassette during execution of a print operation, the paper feed cassette is automatically pushed out a small amount from its installed state. By doing so, the user can quickly confirm that the supply is exhausted without pulling out the paper cassette.
However, in the technology disclosed in JP 2000-313533A, when the image forming apparatus stops during a printing operation, the user can not confirm that the supply is exhausted unless he goes to the location where the image forming apparatus is installed and visually checks the condition of the paper feed cassette. Therefore, when refill paper is stored in a different location than the printer is installed, the user must go to the storage location to get refill paper after going to the installed location of the image forming apparatus and confirming that the supply is exhausted, and again return to the location in which the image forming apparatus is installed.
Also, ordinarily, when an image request signal is given from a terminal on a network to the image forming apparatus, a printer mark (a mark indicating that a print operation is in progress) is displayed on the display of this terminal, but when the user has confirmed that this display has not disappeared for a long time, it is necessary for the user to move to the location where the image forming apparatus is installed and check the reason that the print operation has not completed. That is, after the image forming request signal is given from the terminal to the image forming apparatus, though another operation is being performed on that terminal, this operation must be temporarily interrupted and the reason that the print operation has not completed must be confirmed, worsening operating efficiency.
The present technology was made with the foregoing in mind, and it is an object thereof to provide an image forming apparatus wherein a state is not incurred in which, if a user gives an image forming request when there are few sheets of paper remaining in the paper feed cassette, the supply is exhausted during the image forming operation, and the user must move to the location in which the image forming apparatus is installed and perform a confirmation operation, nor a state in which an operation of the user is temporarily interrupted.